Fishing-tool.



C. MOORE.

FISHING T001..

APPLICATIONHLEDvsEPLzg.1913.

Patented Aug. 31, 1915.

IN VEN TOR, @l and@ M0030@ WI TNESSES A TTORNE Y CLAUDE MOORE, OF TAIET,CALIFORNIA.

FISHING-TOOL.

Specication of Letters Patent.

Patented Aug.. 31, 1915.

Application led September 29, 1913. Serial No. 792.349.

To all whom it may concern.'

Be it known that I, CLAUDE MOORE, a citinia, have invented new anduseful Improvements in Fishing-Tools, of which the following is aspecification.

To recover lost pipes or other objects in deep wells there are commonlyused fishing tools, and of these the most common are what are known asover-shot fishing tools, that is, tools which pass over and entirelysurround a string of pipe and the collars thereon and which can engageall of said vcollars successively as the fishing tool descends. However,so far as I am aware, no over-shot fishing tools has been provided,

' which, after it has been in position to engage a collar, can then bereleased or detached therefrom and drawn upward from the string of pipe.There is great necessity for such a contrivance, because otherwise thefishing tool has often to be recovered either by pulling the pipeasunder or by breaking the shing tool.

It is the object of my present invention tov "provide an over-shotfishing tool which can thus be detached.

In the accompanying drawing, Figure 1 is a side view of a portion of apipe to which my invention is applied, the fishing tool itself beingshown in Avertical section; Fig. 2 is a cross section on the line 2-2 ofFig. 1; Fig. 3 is a perspective view of one of the lugs of the fishingtool.

Referringto the drawing, 1 indicates an ordinary deep well pipe, and 2 acollar therefor, which is here shown as the uppermost, although it mightbe intermediate of a string of pipes. 3 indicates a tube of diametersufliciently large to surround the collar 2, and around the lower end ofthe tube 3 is screwed the upper end of a tubular lug carrier 4. Belowthe upper threaded portion 5 of said lug carrier, which is screwed 'tothe lower end of the tube 3, said lug carrier is internally enlarged indiameter, as shown at 6, and the lowermost portion 7 of the lug carrier4 is internally reduced in di-v ameter. There is thus formed in themediate portion of the lug.- carrier a receptacle for lugs 8, of whichthere may be any number,

'though there are here shown four. These lugs are so shaped that, intheir innermost position, as shown in Fig. 1, they form a rusto-conicalshell. Each lug 1s permanently, although loosely, attached to thecarrier by a screw 9, which is passed outward through a hole 10 in thelug, and screwed intothe carrier, the hole 1() being of such form as topermit a limited movement to and from the lug carrier. The bottom ofeach lug 1s formed with a downward eXtension 11 having outwardly flaringor underveut edges 12, said extensions fitting in similarly shapedrecesses 13 in the inwardly enlarged lower portion 7 ofthe lug carrier.Thus, as the fishing tool descends, and passes over each carrier insuccession, said lugs contacting with the outer surface of the collarsare moved into the recessed mediate portion of the lug carrier. As soonas the lug carrier has descended to such a level that the lugs pass thelower edge of the collar, said lugs are pressed inward byv a circularstretched split steel spring 14, which is contained in registeringgrooves 16 in the lugs, and is movably attached to said lugs by screws17 passing through slots 18 in the spring, and which therefore permitcircumferential movement of the spring. Since said spring is alwaysunder tension, it immediately contracts, when the lugs pass the loweredge of the collar, thereby pressing said lugs inwardly, so that theirupper ends are in contact with the pipe below the collar. When said lugshave been passed below any collar of a string of pipes, and the fishingtool is then raised, the upper lends of the lugs engage the lower edgeof the collar, and the string of pipes can generally be raised thereby.

Now my invention consists in the means which I employ for separating thefishing tool from the string of pipe whenever it is desired to do so,as, for instance, if it-is found impossible to withdraw the string ofpipes. With this object I form threads 19 upon the upper end of eachlug, which threads make a very acute angle with the general direction ofsaid edge, thev inner side of each thread sloping very much moreabruptly than the outer side.l In Order to detach the iishing tool fromthe collar, the tube 3, and therefore also the fishing tool, `is rotatedin the direction toward which the threads slope outward, which is hereshown as a right-handed direction, but may also be left-handed. Sincethe outward directions of said threads make an acute angle with theirdirection of rotation, the result is that the friction against the loweredge of the collar causes said lugs to move outwardly, until eventuallythe upper edges of the lugs escape outward beyond the surface of thecollar, and the fishing tool is easily pulled upward until it arrives atthe next succeeding collar, if there be one, when the operation isrepeated.`

In order to prevent a rocking movement of the lugs about a horizontalaxis passing through the axis of the pipe, I form each'lug with a recess21 at one end 'of its upper edge and a projection 22 at the other endthereof, Awhich projection, when the lugs are in their innermostposition, is adapted, as shown in dotted lines in Fig. l, to it snuglyinto th recess 21 of an adjacent lug.

l. An over-shot shing tool for pipes,

having a lug arranged to pass a lateral projection ,on the pipe toengage the under side of the same, said engaging portion having obliquegrooves, to produce lateral motion of said lug when rotary motion isimparted thereto while in such engagement.

2. A fishing tool for pipes, comprising a lug carrier, lugs movablysupported thereby, and arranged to pass below, and engage the under sideof a projection in the pipe, the upper ends of said lugs having obliquegrooves to cause the lugs to move outward while in engagementl with saidunder side, when rotation is imparted to the lugs.

3. A fishing tool for pipes, comprising a tube arranged to pass theprojections on the pipes, a mediate portion of said tube being recessedinternally, lugs movably received in said recess and secured to thetube, the lower ends of said lugs having depending extensions fitting inrecesses in the lower portion of the tube below said intermediaterecess, and the upper ends of said lugs having oblique grooves toproduce an outward movement of the lugs from a rotary movement of thetube, when said lugs are in engagement with the under side of saidprojection.

4. A fishing tool for pipes, comprising a tube arranged to pass theprojections on the pipes, a mediate portion of said tube being recessedinternally, lugs movably received in said recess and secured to thetube, the lower ends of said lugs having depending extensions fitting inrecesses in the lower portion of the tube below said intermediaterecess, and the upper ends of said lugs having oblique grooves toproduce an outward movement of the lugs from a rotary movement of thetube, when said lugs are in engagement with the under side of saidprojection, and resilient means for moving inwardly the upper parts ofsaid lugs.

y5. A fishing tool for pipes, comprising a tube arranged to pass theprojections on the pipes, a mediate portion of said tube being recessedinternally, lugs movably received in said recess and secured to thetube, the lower ends of said lugs having depending extensions fitting inrecess in the lower portion of the tube below said intermediate recess,the upper parts of said lugs having means coengaging one another tomaintain the lugs in their normal position, and the upper ends of saidlugs having means constructed to produce an outward movement of the lugsfrom a rotary movement of the tube, when said lugs are in engagementwith the under side of said projection.

In testimony whereof I have hereunto set my hand in the presence of twosubscribing` witnesses.

CLAUDE MOORE. Witnesses:

FRANCIS M. WRIGHT, D. B. RICHARDS;

